In the power conversion device, a DC current is converted into an AC current by performing switching by a power semiconductor. The power conversion device possesses a power module which possesses a plurality of power semiconductors, a capacitor module to be connected to a DC bus bar between a DC power source and the power module in parallel with the power module, a drive circuit part which drives the power semiconductors, and a control circuit part which outputs a switching control signal to the drive circuit part and so forth, and these are contained in a metal housing (for example, see Patent Literature 1). In the power conversion device, a heavy electricity system (the power module, the drive circuit part, the capacitor module and so forth) and a light electricity system (the control circuit part) are contained in the same housing in this way.
As described above, since the power semiconductor switches high voltage, electromagnetic noise generates with switching. Therefore, in a conventional power conversion device, a member (a metal plate) which shields the electromagnetic noise to the control circuit part is provided in order to reduce conduction noise to a power supply source of the light electricity system.